ans = input()

if int(ans) >= 30:
    print("Yes")
else:
    print("No") ans = input() ans input() input if int(ans) >= 30:
    print("Yes")
else:
    print("No") int(ans) >= 30 int(ans) int ans 30 print("Yes") print "Yes" print("No") print "No" ans = input() input() ans
ans = input()

if int(ans) >= 30:
    print("Yes")
else:
    print("No")